Comparison of Noise Levels for Water Vapor Radiometers and the Troposphere

Abstract

The Jet Propulsion Lab (JPL) has been appointed as NASA's division for unmanned space flight. Research in Very Long Baseline Interferometry (VLBI) is one aspect important to JPL. One of the largest error sources for work in VLBI is the path delay error caused by water vapor present in the troposphere. Generally, a water vapor radiometer (WVR) is used to measure the effect of the water vapor to improve measurements in VLBI. My project was to make a comparison of water vapor radiometers and to determine over what time periods the water vapor radiometers should be used.